Determining the factors impacting the quality of life among the general population in coastal communities in central Vietnam

People living in coastal areas are frequently affected by natural disasters, such as floods and storms. This study aimed to assess the quality of life (QoL) of people living in disadvantaged coastal communes (subdivision of Vietnam) and identify their associated factors by using the World Health Organization’s quality of life instrument (WHOQOL-BREF). To achieve this, a cross-sectional descriptive study was conducted on 595 individuals aged 18 years and above living in the coastal communes in Thua Thien Hue province, Vietnam, from October 2022 to February 2023. The results showed that the mean overall QoL (mean ± SD) was 61.1 ± 10.8. Among the four domains of QoL, the physical health (57.2 ± 12.3) domain had a lower score than the psychological health (61.9 ± 13.0), social relations (63.4 ± 13.4), and environment (61.9 ± 13.3) domains. The QoL score of the domains for participants affected by flooding was significantly lower than that of those not affected, except for social relations. Multivariable logistic regression showed that subjects with not good QoL had the educational background with no formal education (Odds ratio (OR) = 2.63, 95% CI 1.19–5.83), fairly poor/poor households (OR = 2.75, 95% CI 1.48–5.12), suffered Musculoskeletal diseases (OR = 1.61, 95% CI 1.02–2.56), unsatisfaction with health status (OR = 5.27, 95% CI 2.44–11.37), family conflicts (OR = 4.51, 95%CI 2.10–9.69), and low levels of social support (OR = 2.62; 95% CI 1.14–6.02). The analysis also revealed that workers (OR = 0.17, 95% CI 0.04–0.66) had a better QoL than farmer-fisherman. QoL in disadvantaged coastal communes was low, with the lowest scores in the physical health domain. Based on the socioeconomic factors associated with not good QoL identified here, it is recommended that local authorities take more appropriate and practical measures to increase support, including measures for all aspects of physical health, psychological health, social relations, and the living environment, especially for people affected by floods.


General characteristics
Table 1 shows the general characteristics of the participants and their associations with the overall QoL.Female participants constituted 53.9%, while those aged 60 years and older accounted for 37.0%.Most participants had attended primary school (32.8%), followed by secondary school (31.4%).Most study participants were nonreligious and married, accounting for 78.8% and 90.4% of the sample, respectively.The main profession of the research participants was farming fishermen (47.1%).In addition, research participants living in poor (6.6%) and near-poor (9.9%) households remained.And 16.1% of them were unsatisfied with their current health status.More than half (57.0%) and 19.0% of the study population was affected by storms and floods, respectively.A high level of social support was reported by 91.4% of the participants, while 7.9% experienced family conflicts.Exposure to potentially harmful substances during work was reported by 17.1% of participants.
Table 1 also presents that the QoL of subjects was significantly affected by age, educational background, professions, financial family status, self-assessment of current health status, impact of storms and floods last year, family conflicts, and social support (p < 0.05).

QoL of research participants
Table 2 shows the QoL of the study participants quantified using the WHOQOL-BREF scale.The overall score of QoL was 61.1 ± 10.8.The domain with the highest score was social relationships, at 63.4 ± 13.4, while the physical health domain received the lowest score of 57.2 ± 12.3.Except for social relationships, more than half of the people living in coastal areas did not have good QoL.The QoL score of the domains for people affected by flooding was significantly lower than that of those not affected, except for social relationships.
Table 3 shows the health issues reported by the participants and their associations with their QoL.Health problems with high prevalence at the study sites included musculoskeletal diseases (34.6%) and digestive disorders (21.7%).Respiratory, digestive, dermatological, and musculoskeletal disorders were identified as significant factors affecting QoL (p < 0.05).

Discussion
The present study assessed the QoL and its associated factors among people living in coastal communes in central Vietnam.The findings indicated that 39.3% of research subjects had good QoL, especially those with a low score in the physical health domain.QoL was influenced by educational background, profession, family financial status, musculoskeletal diseases, self-assessment of current health, family conflicts, and social support.To the best of our knowledge, this is the first study to use the WHOQOL-BREF to measure the QoL in the general population of Southeast Asia.
The overall QoL score (61.1 ± 10.8) living in coastal areas was higher than that of people living near solid waste management facilities in Vietnam 14 but lower than the global average 15 .The QoL of the target population in this study was lower than that for the Pakistani and Indonesian populations in all four domains, except environment 16,17 .The low QoL scores obtained in this study could be attributed to unsatisfactory living  16 .Meanwhile, the highest score in the social relationship domain (63.4 ± 13.4), which was also observed in Pakistan 17 .This was probably due to the neighborly relationship creating a strong connection between individuals and communities in coastal areas.This finding is supported by a previous study that revealed a significant positive relationship between social cohesion and QoL 18 .Through living in an area for generations, people become familiar with their neighbors and who can receive assistance for major life events, such as marriage and illness.Interestingly, the QoL score of the domains for people affected by flooding was significantly lower than that of those not affected, except for social relationships.Our findings support previous studies that have confirmed the detrimental effects of flooding on QoL [19][20][21][22][23] .Therefore, to lessen the affects of flooding, it is crucial to offer residents in flood-affected areas psychological counseling as well as physical and environmental supports.
Subjects who were no formal education were likely to have lower QoL than those with high school education and above (OR = 2.63).This finding is supported by previous studies 24,25 , which reported that lower educational levels were related to unhappiness and poor social relationships.
Profession was significantly associated with QoL.This result is consistent with previous studies reporting significant impacts of severe workload, economic categorization, and job pressure [26][27][28] .The stability of workload and income, both of which are closely related to the job, also impact QoL.Reducing work intensity is expected to improve the QoL.
Family financial status is also associated with QoL.People living in low-income households were 2.75 times more likely to have a significantly lower QoL than those living in higher-income households.Family financial was reported to be associated with all domains of QoL except the physical domain (Appendix 2-5).This is consistent with a previous study by Rajput et al. 29 , who argued that the higher socioeconomic status of the study participants helps them have a better QoL .
Although some diseases, such as respiratory, digestive, and dermatological diseases, were identified as significant factors by univariate logistic regression analysis, multivariable logistic regression analysis found that these factors were not associated with QoL, except for musculoskeletal diseases.Previous studies have reported that diseases affect QoL [30][31][32] , necessitating further longitudinal studies to confirm the results obtained for this population.More comprehensively, the present study revealed that people who were dissatisfied with their health were 5.14 times more likely to have a lower QoL than others.Moreover, unsatisfaction with health status was found to be strongly associated with all domains of QoL (Appendix 2-5).This is consistent with previous studies in Iran and Norway, demonstrating that self-reported health status was the most substantial factor for QoL 33,34 .Another study argued that poor health status has a negative impact on QoL 14 , recommending a revision of public health policies in the study areas.www.nature.com/scientificreports/Family environment and social support significantly affected QoL.Frequent conflicts with their families decreased the QoL of the participants (OR = 4.25), similar to a study in Malaysia that reported that work-family conflict was associated with QoL 35 .Besides, with the exception of the psychological domain, family conflict was found to be related to all QoL domains (Appendix 2-5).A low level of social support decreased QoL (OR = 2.56).Social support, which has the potential to improve QoL in target communities, has been reported as a QoL predictor in previous studies 35,36 .

Strengths and limitations
The main limitation of this cross-sectional study was the difficulty in investigating QoL and its related factors over a long period, although QoL is highly variable over time.For example, the temporal change in QoL after a flood event, which would gradually recover, could not be analyzed in this study.
One of the advantages of this study was the use of a validated and standardized WHOQOL-BREF scale, which enabled a comparison of the obtained QoL with other reports.Another advantage was the analysis of communitybased QoL, especially focusing on healthy people living in coastal areas, whereas most previous studies analyzed QoL only in diseased and handicapped populations.This study contributes to a better understanding of the QoL of people in monsoon Asia affected by frequent floods and storms, which has been poorly investigated.

Conclusion
To the best of our knowledge, this was the first study to analyze QoL and its association with sociodemographic variables and the impact of floods on the general Vietnamese population.Overall, the QoL of residents in disadvantaged communes in coastal areas was low, with only 39.3% of the participants having a good QoL.Among the four domains of the WHOQOL-BREF scale, the physical health domain showed the lowest score (57.2 ± 12.3), while the social participation domain had the highest score (63.4 ± 13.4).The QoL score in all domains was notably lower for individuals impacted by flooding compared to those who were unaffected, with the exception of social relationships.Farmer-fishermen, low income, musculoskeletal diseases, dissatisfaction with their current health status, family conflicts, and less social support contributed to lower QoL.
QoL, especially in terms of physical health, in the general population has not received much attention.This study demonstrated that a challenging economic climate, inadequate medical facilities and services, and the risk of numerous natural disasters, such as floods, are contributing factors to the lower QoL.Local authorities need to take more appropriate and practical measures to increase their support, including all aspects of physical and mental health, social relations, and living environments, to improve the QoL of people living in these problematic communes.

Study design and setting
A cross-sectional descriptive study was conducted in coastal communes with disadvantages as described below in Thua Thien Hue province, central Vietnam.This province has a tropical monsoon climate with 3000 mm of annual rainfall on average.Floods generally begin in October, followed by the rainy season in September.According to the Decision of the Prime Minister of Vietnam, Thua Thien Hue Province has seven communes that have been approved as poor communes with particular challenges in the lowlands, coastal areas, and islands of Vietnam for the period of 2021-2025.These seven communes have an approximate population of 45,000 and a rate of poor and fairly poor households of 15% or more or are affected by salinity intrusion continuously for three months or more during the year and have a rate of poor and fairly poor households (e.g.income of 1,500,000 VND (~ 61 USD)/person/month and lack of basic social services including employment, health, education, housing, water and sanitation, and information) of 12% or more 37,38 .
This study employed the following multistage sampling method: Two of the seven poor communes were selected randomly: Giang Hai in Phu Loc district and Phu Gia in Phu Vang district.From the selected communes, four villages were randomly selected.The chosen villages included Giang Che village and Nam Truong village in the Giang Hai commune and Ha Tru Thuong and Mong B villages in the Phu Gia commune.

Subjects
The required study sample size was calculated as follows: 39 where p was set at 0.50 because the proportion of subjects with good QoL was unknown 40 , d was set at 0.05 as a desired error 40 , and Z 1−α/2 for reliability was set at 1.95 with 95% confidence (alpha = 0.05).This equation set the minimum sample size at 384.A larger sample (n = 595) was selected based on the following criteria: (a) 18 years old or older, (b) present during the study period, (c) lived continuously at the study sites for at least 12 months before the study, and (d) willing to participate in the study.Patients with mental health problems were excluded.

Table 1 .
General characteristics of the research subjects (n = 595) and the association with overall quality of life.The numbers in the parentheses mean the percentages.Significant values are in bold.

Table 2 .
Quality of life of research participants quantified using the WHOQOL-BREF scale by flood(n = 595).*Compared QoL (Mean score) of the subjects affected and non affected flood with p < 0.05 using Mann-Whitney U Test.

Table 3 .
Health issues of the research subjects (n = 595) and the association quality of life.The numbers in the parentheses mean the percentages.Significant values are in bold.

Table 4 .
Results of logistic regression analysis to identify factors associated significantly with not good QoL of research subjects with all domains of QoL BREF.Ref, Reference; OR, Odds ratio.Significant values are in bold.